Brightness enhancement film for backlit image displays
US7286280B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 16, 2005 |
| Grant date | Oct 23, 2007 |
| Priority date | — |
| Expiry date | Mar 16, 2025 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B3/0062
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A brightness enhancement film having a monolayer of approximately hemispherical, transparent, closely packed larger diameter hemi-beads. Due to the hemi-beads' hemispherical shape, gaps remain between adjacent ones of the larger diameter hemi-beads. A substantial number of the gaps are provided with at least one approximately hemispherical, transparent hemi-bead having a diameter substantially less than the diameter of the larger diameter hemi-beads. Provision of smaller diameter hemi-beads within the gaps increases the film's reflectance value, such that the film's apparent brightness declines as a relatively smooth, continuous function of viewing angle, for viewing angles ranging from 0° (normal incidence) to about 40°, which is the preferred angular viewing range.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.